O2 Sensor Disconnected During Tuning

[dori34]

Hi Guys, my tuner disconnected the o2 sensor whilst tuning and forgot to connect it back after he was done with it.

I have since connected it back up and now the car idles funny when warm & backfires alot.

Would this have caused any issues because he tuned it when the o2 sensor was disconnected or would it be a totally unrelated problem ?

He also tuned it without a bov (blocked it off) but i got a GTR bov on there atm but i dont have the correct plumb back pipe so he blocked it, after i plumb it all up and get it running, would this affect the tune/cars drivebility & idle in anyway?

any help much appreciatyed.

Cheers

[Pal]

i had mine tuned a couple of weeks ago and my tuner mentioned he turns off the o2 sensor when tuning too?

[dori34]

well i guess its gotta be done,

i think my bov may be leaking slightly & causing this problem, ill double check that on the weekend

[Dose Pipe Sutututu]

What ECU are you using?

you should be always tuning with the O2 switched off!

if its a powerFC, go into the settings menu, and disable it see how you go, if not enable it if it's disabled see how you go

[Dose Pipe Sutututu]

saying that, O2 only affects cruise, where the computer readjusts the fuel map when cruising, on load the O2 does nothing.

[Brezza]

i believe that the O2 sensor only trims the mixtures at cruise.

when tuning you turn the sensor off or you could unplug it. this allows the computer to not trim the mixtures and you get a true readout of what air fuel ratio you have.

but when youre under load the O2 sensor does nothing.

i am not running any at the moment in my GTR, still waiting on Nissan to get some in. the car runs fine, chews through a little more fuel than it should when cruising but other than that no difference.

[JonnoHR31]

yep o2 trims fuel when you stay in the same load cell for a prolonged period. when tuning light load stuff you must turn off the o2 sensor to get the afr's right

[paulr33]

its normal to turn off 02 feedback during tuning

but it should be re-enabled, the powerfc faq in my sig covers how to enable and check it

the blocked bov would make it stall and run like ass, fix that

[dori34]

im running a emanage ultimate.

oh ok fair enough, well its strange how the car idles funny when warm after connecting the 02 back up lol

ill get the bov sorted this weekend and see how it goes.

thanks guys

[STATUS]

im running a emanage ultimate.

oh ok fair enough, well its strange how the car idles funny when warm after connecting the 02 back up lol

ill get the bov sorted this weekend and see how it goes.

thanks guys

you cant turn feedback off with the ultimate so he may have tuned "around" it, leave it disconnected and run a tank through the car if your economy is fine leave it disconnected. I have on occasions had to do the same thing when a crook 02 sensor keeps 'pulling' the mixtures out of whack.

[dori34]

yeap thats what i did when i first got the car back.

drove a full tank to work and back with the occasional hit here & there and i managed to get like 350km

is that reasonable?